1. Field of the Invention
The present invention relates to a light source apparatus that emits a plurality of beams, a recording apparatus installed with the light source apparatus, and an image forming apparatus installed with the recording apparatus, these apparatuses being applicable to an image setter or plotter apparatus for use in various types of plate making such as CTP (Computer to Plate), and for creating art work film or mask film and printed circuit boards, an image forming apparatus using silver salt as a medium, a DI (Direct Imaging) machine, an electrophotographic apparatus, a printer, a copier, a plate making apparatus, a printing machine having a plate making function, and so on.
2. Description of the Background Art
A light source apparatus comprising a plurality of anode common light source elements (laser diodes, for example), lenses corresponding to each light source element, one or a plurality of insulators for holding the light source elements, a metal bracket for holding the insulator, and a circuit board to which terminals of the respective light source elements, which are fixed to the metal bracket, are connected, is disclosed in paragraph 0079, FIG. 19, and soon of Japanese Unexamined Patent Application Publication 2005-317925, for example. In this light source apparatus, when a set of components comprising a light source element for outputting a single beam, a lens, an insulator, a terminal, and soon is referred to as an optical member, a plurality of optical members are formed on the circuit board, and by varying the number and arrangement of the circuit boards, a light source apparatus for use in numerous applications, image writing in many lengths, and so on can be provided.
Hence, in a conventional light source apparatus, a plurality of optical members are divided among and arranged on a plurality of circuit boards, and by varying the number of circuit boards, it is possible to manufacture light source apparatuses in many lengths. Further, broken light sources can be replaced in circuit board units, enabling a reduction in maintenance costs. Thus, a conventional light source apparatus exhibits various possibilities.
In actuality, however, it has been learned that the number of beams must be varied in single beam units. The background to this is demand for light source apparatus structures of many lengths and improvements in maintenance ease. Demand for reductions in initial cost and maintenance cost must also be satisfied. For example, conventionally, a single circuit board can carry a large number of light sources, and hence it is difficult to use the circuit board effectively when light source apparatuses having different numbers of light sources are manufactured.
For example, when manufacturing a light source apparatus comprising 84 light sources using a circuit board that carries 36 light sources, three circuit boards must be used, with the result that 108 light sources are provided. However, the number of light sources in actual use is 84, and therefore substrate costs are used wastefully. When a large number of light sources are fixed directly to the circuit board (in the aforementioned publication, caulking is recommended), for example when a single board is capable of carrying 36 light sources, as in the example described above, and a single light source breaks, the remaining 35 usable light sources must be replaced together with the board, and therefore the cost of replacement components is particularly high.
When studying the background art in view of the problems described above, according to which a conventional apparatus must be manufactured in unnecessary beam number units or a circuit board carrying a plurality of light sources must be replaced, it is evident that conventional apparatuses are extremely wasteful.